You said you were thinking of a Nacra 5.7 and carrying two on occasion. My brother and I had a Nacra 5.7 for years on Chick's Beach (Virginia Beach) in the early 90s. There were sandbars all over the place. I thought it was a cool boat: big giant trampoline, not too many strings to pull, no boards, double trapeze, hard to pitch, and it seemed to go plenty fast. At 185lb I bet you could get it back over with a water bag.